1. Field of the Technology
The present technology relates to a control method of driving toner containers and an image forming apparatus using the drive control method.
2. Description of the Prior Art
Recently, there have been increased demands for image forming apparatuses capable of high-speed operations, and as the number of printing (per unit time) increases the speed of the paper to be conveyed has been also enhanced. For example, conventionally the processing ability of an image forming apparatus with not lower than 60 sheets per minute (A4 short-edge feed) was previously regarded as a high-speed machines, but nowadays, the situation has changed and the machines having a processing speed of 80 sheets per minute or greater should be regarded as high-speed ones, and further, machines having a speed of 100 sheets per minute are being developed.
Since a large amount of toner is consumed in these image forming apparatuses, most of the developing units have adopted a configuration including a plurality of toner containers arranged therein, wherein the toner supplied from each toner container is not directly fed to the developing hopper but is once collected in a toner feed device that functions as a “relay box”, then is fed into the developing hopper as the toner concentration therein becomes lower, in order to keep the toner concentration in the developing hopper constant and avoid indication of “toner empty” from occurring even when a large volume of printing has been performed (see patent document 1: Japanese Patent Application Laid-open Hei 03-220577).
There is an apparatus configuration with the above toner supply method, which employs a technique whereby a plurality of toner containers are arranged at locations away from the developing unit and print processor and the apparatus can continue its print processing step even if one of the toner containers which has been detected as being empty is being replaced.
According to this toner supply method, even if the content of the toner container is used up, the toner in the relay box can be supplied so as to permit continuation of the printing job in progress. However, this method entails the problem that it is troublesome for the user to replace the toner container and that there is a need to devise a countermeasure to prevent toner from scattering inside the machine.